[5/8] xfs_db: access arbitrary realtime blocks and extents

Commit Message

Darrick J. Wong Oct. 31, 2024, 11:22 p.m. UTC

From: Darrick J. Wong <[e-mail]>

Add two commands to xfs_db so that we can point ourselves at any
arbitrary realtime block or extent.

Signed-off-by: Darrick J. Wong <[e-mail]>
Reviewed-by: Christoph Hellwig <[e-mail]>
---
 db/block.c        |  109 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 man/man8/xfs_db.8 |   22 +++++++++++
 2 files changed, 131 insertions(+)

Patch

diff --git a/db/block.c b/db/block.c
index 87118a4751ef94..79ae0ea5802a83 100644
--- a/db/block.c
+++ b/db/block.c
@@ -25,6 +25,10 @@  static int	dblock_f(int argc, char **argv);
 static void     dblock_help(void);
 static int	fsblock_f(int argc, char **argv);
 static void     fsblock_help(void);
+static int	rtblock_f(int argc, char **argv);
+static void	rtblock_help(void);
+static int	rtextent_f(int argc, char **argv);
+static void	rtextent_help(void);
 static void	print_rawdata(void *data, int len);
 
 static const cmdinfo_t	ablock_cmd =
@@ -39,6 +43,12 @@  static const cmdinfo_t	dblock_cmd =
 static const cmdinfo_t	fsblock_cmd =
 	{ "fsblock", "fsb", fsblock_f, 0, 1, 1, N_("[fsb]"),
 	  N_("set address to fsblock value"), fsblock_help };
+static const cmdinfo_t	rtblock_cmd =
+	{ "rtblock", "rtbno", rtblock_f, 0, 1, 1, N_("[rtbno]"),
+	  N_("set address to rtblock value"), rtblock_help };
+static const cmdinfo_t	rtextent_cmd =
+	{ "rtextent", "rtx", rtextent_f, 0, 1, 1, N_("[rtxno]"),
+	  N_("set address to rtextent value"), rtextent_help };
 
 static void
 ablock_help(void)
@@ -104,6 +114,8 @@  block_init(void)
 	add_command(&daddr_cmd);
 	add_command(&dblock_cmd);
 	add_command(&fsblock_cmd);
+	add_command(&rtblock_cmd);
+	add_command(&rtextent_cmd);
 }
 
 static void
@@ -302,6 +314,103 @@  fsblock_f(
 	return 0;
 }
 
+static void
+rtblock_help(void)
+{
+	dbprintf(_(
+"\n Example:\n"
+"\n"
+" 'rtblock 1023' - sets the file position to the 1023rd block on the realtime\n"
+" volume. The filesystem block size is specified in the superblock and set\n"
+" during mkfs time.\n\n"
+));
+}
+
+static int
+rtblock_f(
+	int		argc,
+	char		**argv)
+{
+	xfs_rtblock_t	rtbno;
+	char		*p;
+
+	if (argc == 1) {
+		if (!iocur_is_rtdev(iocur_top)) {
+			dbprintf(_("cursor does not point to rt device\n"));
+			return 0;
+		}
+		dbprintf(_("current rtblock is %lld\n"),
+			xfs_daddr_to_rtb(mp, iocur_top->off >> BBSHIFT));
+		return 0;
+	}
+	rtbno = strtoull(argv[1], &p, 0);
+	if (*p != '\0') {
+		dbprintf(_("bad rtblock %s\n"), argv[1]);
+		return 0;
+	}
+	if (rtbno >= mp->m_sb.sb_rblocks) {
+		dbprintf(_("bad rtblock %s\n"), argv[1]);
+		return 0;
+	}
+	ASSERT(typtab[TYP_DATA].typnm == TYP_DATA);
+	set_rt_cur(&typtab[TYP_DATA], xfs_rtb_to_daddr(mp, rtbno), blkbb,
+			DB_RING_ADD, NULL);
+	return 0;
+}
+
+static void
+rtextent_help(void)
+{
+	dbprintf(_(
+"\n Example:\n"
+"\n"
+" 'rtextent 10' - sets the file position to the 10th extent on the realtime\n"
+" volume. The realtime extent size is specified in the superblock and set\n"
+" during mkfs or growfs time.\n\n"
+));
+}
+
+/*
+ * Move the cursor to a specific location on the realtime block device given
+ * a linear address in units of realtime extents.
+ */
+static int
+rtextent_f(
+	int		argc,
+	char		**argv)
+{
+	xfs_rtblock_t	rtbno;
+	xfs_rtxnum_t	rtx;
+	char		*p;
+
+	if (argc == 1) {
+		if (!iocur_is_rtdev(iocur_top)) {
+			dbprintf(_("cursor does not point to rt device\n"));
+			return 0;
+		}
+
+		rtbno = xfs_daddr_to_rtb(mp, iocur_top->off >> BBSHIFT);
+		dbprintf(_("current rtextent is %lld\n"),
+				xfs_rtb_to_rtx(mp, rtbno));
+		return 0;
+	}
+	rtx = strtoull(argv[1], &p, 0);
+	if (*p != '\0') {
+		dbprintf(_("bad rtextent %s\n"), argv[1]);
+		return 0;
+	}
+	if (rtx >= mp->m_sb.sb_rextents) {
+		dbprintf(_("bad rtextent %s\n"), argv[1]);
+		return 0;
+	}
+
+	rtbno = xfs_rtx_to_rtb(mp, rtx);
+	ASSERT(typtab[TYP_DATA].typnm == TYP_DATA);
+	set_rt_cur(&typtab[TYP_DATA], xfs_rtb_to_daddr(mp, rtbno),
+			mp->m_sb.sb_rextsize * blkbb, DB_RING_ADD, NULL);
+	return 0;
+}
+
 void
 print_block(
 	const field_t	*fields,
diff --git a/man/man8/xfs_db.8 b/man/man8/xfs_db.8
index f50ac949be0189..48afcb6e81787b 100644
--- a/man/man8/xfs_db.8
+++ b/man/man8/xfs_db.8
@@ -1099,6 +1099,28 @@  .SH COMMANDS
 Exit
 .BR xfs_db .
 .TP
+.BI "rtblock [" rtbno ]
+Set current address to the location on the realtime device given by
+.IR rtbno .
+This value must be a realtime block number.
+If no value for
+.I rtbno
+is given the current address is printed, expressed as an rtbno.
+The type is set to
+.B data
+(uninterpreted).
+.TP
+.BI "rtextent [" rtxno ]
+Set current address to the location on the realtime device given by
+.IR rtextent .
+This value must be a linear address in units of realtime extents.
+If no value for
+.I rtextent
+is given the current address is printed, expressed as an rtextent.
+The type is set to
+.B data
+(uninterpreted).
+.TP
 .BI "ring [" index ]
 Show position ring (if no
 .I index